Abstract: Rate of embryo formation in Gossypium hirsutumL. (2n = 4x = 52) ×G. arboreum L.(2n = 2x = 26)F₀generation is mainly affected by female parent, G. hirsutum. There is significant difference among the varieties. 6901 and Chaoyang No. 1, have high embryo formation rate and high general combining ability in weight of unginned cotton per bell, number of seed per bell and seed index, But 6913 and Heishan cotton, which have low embryo formation rate, have low general combining ability in above traits, too. Among the 7 varieties of G. arboreum we used, Shulu-baihua and Wanzi have high embryo formation rate and high general combining ability in seed index. So it can greatly increase the embryo formation rate in interspecies crossing, using G.hirsutum variety as female parent, which has high general combining ability in weight of unginned cotton per bell, number of seed per bell and seed index, and G. arboreum variety as male parent, which has high general combining ability in seed index.

Key words: Gossypium hirsutum L, G. arboreum L., Interspecies crossing, Embryo orma-tion rate, Combining ability